Heat exchanger manifold improvements for transient start-up

ABSTRACT

A heat exchanger configured to condition a flow of fluid therein. The heat exchanger includes a first manifold, a second manifold, and a conditioning assembly having a plurality of tubular elements extending between the first manifold and the second manifold. The first manifold includes a first end having an inlet formed therein and a second end formed opposite the first end, wherein a generally tapered portion of the second end of the first manifold and a fluid drain feature formed in the generally tapered portion of the first manifold are configured to minimize an amount of the first fluid remaining in at least one of the first manifold and the tubular elements after operation of the heat exchanger.

FIELD OF THE INVENTION

The present invention relates generally to a heat exchanger and, more particularly, to a heat exchanger manifold with for transient start.

BACKGROUND OF THE INVENTION

Conventional radiators are usually provided with a cooling portion in which a radiator liquid is cooled, and two manifolds which are connected to the cooling portion at opposite ends. The first manifold receives the heated radiator liquid before it is led into the cooling portion. The second manifold receives the radiator liquid after it has passed through the cooling portion. The cooling portion usually includes a plurality of tubular elements arranged in parallel which lead the radiator liquid between the manifolds. Surrounding air flows in spaces between the tubular elements so that the radiator liquid is subjected to cooling within the tubular elements. Heat transfer elements of various kinds, e.g. in the form of thin folded fins, are usually arranged in the spaces between the tubular elements to provide an increased contact surface with the air which flows in the spaces between the tubular elements. The tubular elements and the heat transfer elements may be made of metals such as aluminum, copper, brass and magnesium or other materials which have desirable heat-conducting characteristics. Conventional manifolds are usually made of injection-molded plastic material.

One drawback of such conventional radiators is poor heat exchange efficiency, especially during cold start-up transients. During a cold start-up in cold ambient conditions, the cooled radiator liquid, which remained within the first manifold and the tubular elements after operation of the radiator, typically has a temperature of about −20° C. Whereas, the heated radiator liquid entering the radiator typically has a temperature of about 110° C. The heated radiator liquid is introduced into a first end of the first manifold through an inlet and a flow momentum causes the heated radiator liquid to contact a back wall of the first manifold. The back wall directs the radiator liquid downward, causing the tubular elements adjacent the inlet to receive the heated radiator liquid which leads to difficulty in introduction of the heated radiator liquid into the tubular elements adjacent a second end of the first manifold, especially during the cold start up. As the heated radiator fluid flows through the first manifold, the heated radiator liquid mixes with the cooled radiator liquid in the second end of the first manifold. The cooled radiator liquid cools the heated radiator liquid, increasing a viscosity thereof, and thereby minimizing the flow of the first fluid through the tubular elements adjacent the second end of the first manifold. Because the heated radiator liquid is unable to flow through the tubular elements adjacent the second end of the first manifold, a temperature imbalance develops between the tubular elements adjacent the first end of the first manifold and the tubular elements adjacent the second end of the first manifold. As a result of the temperature imbalance, severe thermal stresses may occur which can potentially damage the first manifold, the tubular elements adjacent the second end of the first manifold, and/or a joint formed between the first manifold and the tubular elements.

It would be desirable to produce a radiator which is configured to substantially uniformly distribute a radiator liquid, wherein a structural complexity and a package size thereof are minimized.

SUMMARY OF THE INVENTION

In concordance and agreement with the present disclosure, a radiator which is configured to substantially uniformly distribute a radiator liquid, wherein a structural complexity and a package size thereof are minimized, has surprisingly been discovered.

In one embodiment, a heat exchanger, comprises: a conditioning assembly including a plurality of tubular elements configured to receive a flow of a fluid therein, each of the tubular elements having an inlet opening and an outlet opening formed therein; and a manifold coupled to the conditioning assembly, the manifold including a first end having an inlet formed therein and a second end opposite the first end, wherein the manifold is formed by at least one wall, and wherein a generally tapered portion of the manifold and a fluid drain feature located in the generally tapered portion of the manifold are configured to minimize an amount of the fluid remaining in at least one of the manifold and the tubular elements after operation of the heat exchanger, and wherein at least one of a volume of the generally tapered portion of the manifold and a distance between an inner surface of a wall opposite the inlet openings of the tubular elements and a plane generally defined by the inlet openings of the tubular elements generally decreases along the generally tapered portion of the manifold as a distance from the inlet increases.

In another embodiment, a heat exchanger, comprises: a conditioning assembly including a plurality of tubular elements configured to receive a flow of a fluid therein, each of the tubular elements having an inlet opening and an outlet opening formed therein; and a manifold coupled to the conditioning assembly, the manifold including a first end having an inlet formed therein and a second end opposite the first end, wherein the manifold is formed by at least one wall, and wherein a generally tapered portion of the second end of the manifold is configured to minimize an amount of the fluid remaining in at least one of the manifold and the tubular elements after operation of the heat exchanger, and wherein at least one of a volume of the generally tapered portion of the second end of the manifold and a distance between an inner surface of a wall opposite the inlet openings of the tubular elements and a plane generally defined by the inlet openings of the tubular elements generally decreases along the generally tapered portion of the manifold as a distance from the inlet in a general direction of the flow of the fluid through the manifold increases, and wherein the manifold further includes a fluid drain feature extending laterally outwardly from the generally tapered portion of the second end of the manifold.

In a further embodiment, a heat exchanger, comprises: a conditioning assembly including a plurality of tubular elements configured to receive a flow of a fluid therein, each of the tubular elements having an inlet opening and an outlet opening formed therein; and a manifold coupled to the conditioning assembly, the manifold including a first end having an inlet formed therein and a second end opposite the first end, wherein the manifold is formed by at least one wall, and wherein at least one of a generally tapered first portion of the first end of the manifold and a generally tapered second portion of the second end of the manifold is configured to minimize an amount of the fluid remaining in at least one of the manifold and the tubular elements after operation of the heat exchanger, and wherein at least one of a rate of change in a volume of the generally tapered first portion is less than a rate of change in a volume of the generally tapered second portion and a rate of change in a distance between an inner surface of a wall opposite the inlet openings of the tubular elements which defines the generally tapered first portion and a plane generally defined by the inlet openings of the tubular elements is less than a rate of change in a distance between an inner surface of a wall opposite the inlet openings of the tubular elements which defines the generally tapered second portion and the plane generally defined by the inlet openings of the tubular elements.

BRIEF DESCRIPTION OF THE DRAWINGS

The above, as well as other objects and advantages of the invention, will become readily apparent to those skilled in the art from a reading of the following detailed description of the invention when considered in the light of the accompanying drawings in which:

FIG. 1 is an elevational view of a heat exchanger according to an embodiment of the present invention including a first manifold, a second manifold, and conditioning assembly, wherein a portion of the first manifold is cutaway; and

FIG. 2 is an elevational view of a heat exchanger according to another embodiment of the present invention including a first manifold, a second manifold, and conditioning assembly, wherein a portion of the first manifold is cutaway.

DETAILED DESCRIPTION OF THE INVENTION

The following detailed description and appended drawings describe and illustrate various exemplary embodiments of the invention. The description and drawings serve to enable one skilled in the art to make and use the invention, and are not intended to limit the scope of the invention in any manner.

FIG. 1 depicts a heat exchanger 10 according to the present invention. The heat exchanger 10 shown is a radiator to be used in a vehicle (not shown). The heat exchanger 10 conditions a first fluid (i.e. a radiator liquid), which circulates in a fluid-conditioning system (not shown), using a second fluid (i.e. surrounding air). The fluid-conditioning system may be used to cool an engine (not shown) which powers the vehicle. Those skilled in the art will appreciate that the heat exchanger 10 can be used in various other fluid-conditioning systems, e.g. heating systems, cooling systems, and combination heating/cooling systems, related and unrelated to vehicle applications if desired.

The heat exchanger 10 includes a first manifold 12, a second manifold 14, and a conditioning assembly 16 extending between the first manifold 12 and the second manifold 14. Each of the first manifold 12 and the second manifold 14 can be formed from any material and by any process as desired. In certain embodiments, the first manifold 12 and the second manifold 14 are formed by injection-molding a plastic material. In other embodiments, the first manifold 12 may be formed from a material of sufficient strength so that a wall thickness of the first manifold 12 can be minimized, thereby enhancing heat transfer between the first fluid in the first manifold 12 and the second fluid. For example, the first manifold 12 can be formed from aluminum, which is a material with desirable heat-conducting characteristics and sufficient strength characteristics. Various other materials can be used to form the first manifold 12 and the second manifold 14 if desired.

An inlet 18 of the first manifold 12 is in fluid communication with the fluid-conditioning system and receives the first fluid which has been heated by an external component (i.e. the engine) thereof. The heated first fluid flows through the first manifold 12 and into the conditioning assembly 16. The conditioning assembly 16 shown includes a plurality of tubular elements 20 extending between the first manifold 12 and the second manifold 14. An inlet opening 21 and an outlet opening (not shown) of each of the tubular elements 20 is fluidly connected to the first manifold 12 and the second manifold 14, respectively. The tubular elements 20 are arranged in parallel and spaced apart at substantially equal distances so that substantially constant gaps 22 are formed between adjacent tubular elements 20.

The second fluid flows through the gaps 22 between the tubular elements 20 to cool the heated first fluid flowing through the tubular elements 20. The flow of the second fluid through the conditioning assembly 16 may be caused by a movement of the vehicle and/or by a device which causes the second fluid to flow through the conditioning assembly 16 of the heat exchanger 10 such as a fan, for example. In certain embodiments, the gaps 22 may be provided with at least one heat transfer element 24. Various heat transfer elements 24 can be employed such as thin folded metal elements or fins, for example. The heat transfer elements 24 are arranged to abut the tubular elements 20, thereby increasing a contact surface of the tubular elements 20 with the second fluid to maximize a heat transfer from the first fluid to the second fluid. Each of the tubular elements 20 and the heat transfer elements 24 can be formed from any suitable material such as a metal (e.g. aluminum, copper, brass, magnesium, etc.) or other materials which have desired heat-conducting characteristics. The second manifold 14 receives the cooled first fluid from the respective tubular elements 20 of the conditioning assembly 16, after which the cooled first fluid is discharged from the second manifold 14 to the fluid-conditioning system via an outlet 26.

As illustrated, the first manifold 12 has a generally rectangular shape and includes a first end 46 and a second end 48. It is understood, however, that the first manifold 12 can have any shape and size as desired. In certain embodiments, the first manifold 12 includes a pair of opposing end walls 50, 52, a pair of opposing side walls 54, 56, and a back wall 58 opposite the inlet openings 21 of the tubular elements 20. The walls 50, 52, 54, 56, 58 define an opening configured to receive a portion of the conditioning assembly 16 and a chamber 59 configured to receive the first fluid therein.

As illustrated, a generally tapered portion 60 of the first manifold 12 is configured to distribute at least a portion of the first fluid into the tubular elements 20 adjacent the second end 48 of the first manifold 12. The generally tapered portion 60 is also configured to increase a velocity of the flow of the first fluid into the tubular elements 20 adjacent the second end 48 of the first manifold 12. As a non-limiting example, the generally tapered portion 60 is configured to distribute and increase the velocity of at least a portion of the first fluid flowing into the last ten (10) tubular elements 20 in respect of a general direction of flow of the first fluid through the first manifold 12. The configuration of the generally tapered portion 60 of the first manifold 12 advantageously minimizes an amount of the first fluid remaining within the first manifold 12 and the tubular elements 20 after operation of the heat exchanger 10. Thus, the configuration of the generally tapered portion 60 militates against an accumulation of cooled first fluid within the first manifold 12 and the tubular elements 20, and thereby ensures that the heated first fluid is able to flow through the second end 48 of the first manifold 12 and the tubular elements 20 adjacent thereof. As such, a difference in temperature between the tubular elements 20 adjacent the first end 46 of the first manifold 12 and the tubular elements 20 adjacent the second end 48 of the first manifold 12 is minimized. As a result, a potential for severe thermal stresses which may cause damage to the heat exchanger 10 is minimized.

In certain embodiments, a volume of the generally tapered portion 60 of the first manifold 12 generally decreases in respect of the general direction of flow of the first fluid through the first manifold 12. Accordingly, the volume of the generally tapered portion 60 adjacent the first end 46 is greater than the volume of the generally tapered portion 60 adjacent the second end 48 thereof. It is understood that a rate of change of the volume of the generally tapered portion 60 of the first manifold 12 can be variable or substantially constant as shown.

In other embodiments, a distance between an inner surface 62 of the back wall 58 which at least partially forms the generally tapered portion 60 of the first manifold 12 and a plane A generally defined by the inlet openings 21 of the tubular elements 20 generally decreases along the generally tapered portion 60 as a distance from the inlet 18 in the general direction of flow of the first fluid in the first manifold 12 increases. Accordingly, the distance between the inner surface 62 of the back wall 58 of the generally tapered portion 60 adjacent the first end 46 thereof and the plane A generally defined by the inlet openings 21 of the tubular elements 20 is greater than the distance between the inner surface 62 of the back wall 58 of the generally tapered portion 60 of the first manifold 12 adjacent the second end 48 thereof and the plane A generally defined by the inlet openings 21 of the tubular elements 20. It is understood that a rate of change in the distance between the inner surface 62 of the back wall 58 and the plane A generally defined by the inlet openings 21 of the tubular elements 20 can be variable or substantially constant as shown in FIG. 1.

A fluid drain feature 70 may be formed in the generally tapered portion 60 of the first manifold 12. As illustrated, the fluid drain feature 70 is integrally formed with the generally tapered portion 60 of the first manifold 12. However, those skilled in the art will appreciate that the fluid drain feature 70 can be separately formed from the first manifold 12 if desired. It is also understood that the fluid drain feature 70 can be formed elsewhere in the heat exchanger 10 if desired. The fluid drain feature 70 can be formed with the generally tapered portion 60 of the first manifold 12 by any suitable forming process such as an injection-molding forming process, for example. In certain embodiments, the fluid drain feature 70 is a portion 71 of the back wall 58 extending laterally outwardly from the generally tapered portion 60 of the fluid manifold 12. The portion 71 of the back wall 58 shown is contoured to define a cavity 72. An aperture 74 is formed in the back wall 58 to permit the first fluid to flow, either directly or through an external component (i.e. fitting) or system, from the cavity 72 to a collection tank (not shown). In certain embodiments, the portion 71 of the back wall 58 at least partially surrounds the aperture 74. As illustrated, a hydraulic diameter of the cavity 72 is substantially the same as a hydraulic diameter of the aperture 74, thereby minimizing a volume of the cavity 72. The fluid drain feature 70 is configured to minimize the volume of the cavity 72 in order to minimize an amount of the first fluid remaining in the cavity 72 after operation of the heat exchanger 10. As discussed hereinabove, minimizing the amount of first fluid remaining in the first manifold 12 advantageously militates against an accumulation of cooled first fluid within the first manifold 12 and the tubular elements 20, and thereby ensures that the heated first fluid is able to flow through the second end 48 of the first manifold 12 and the tubular elements 20 adjacent thereto. As a result, the potential for severe thermal stresses which may cause damage to the first manifold 12, the tubular elements 20 adjacent the second end 48 of the first manifold 12, and/or a joint formed between the first manifold 12 and the tubular elements 20 is further minimized.

During operation of the heat exchanger 10, a heated first fluid from the fluid-conditioning system is received into the chamber 59 of the first manifold 12 through the inlet 18. As the first fluid flows from the first end 46 of the first manifold 12 through the chamber 59 and into the second end 48 of the first manifold 12, the generally tapered portion 60 of the first manifold 12 directs and increases the velocity of the flow of the first fluid into the tubular elements 20 adjacent thereto. The generally tapered portion 60 of the first manifold 12 ensures that at least a portion of the heated first fluid flows into the inlet openings 21 of the tubular elements 20 adjacent the second end 48 of the first manifold 12. Once the first fluid flows into the tubular elements 20 of the conditioning assembly 16, the first fluid undergoes a main conditioning by the second fluid flowing through the conditioning assembly 16. The conditioned first fluid then flows from the conditioning assembly 16 through the outlet openings thereof into the second manifold 14. The conditioned first fluid is then discharged from the heat exchanger 10 through the outlet 26 into the fluid-conditioning system.

FIG. 2 depicts a heat exchanger 100 according to another embodiment of the present invention. The heat exchanger 100 shown is a radiator to be used in a vehicle (not shown). The heat exchanger 100 conditions a first fluid (i.e. a radiator liquid), which circulates in a fluid-conditioning system (not shown), using a second fluid (i.e. surrounding air). The fluid-conditioning system may be used to cool an engine (not shown) which powers the vehicle. Those skilled in the art will appreciate that the heat exchanger 100 can be used in various other fluid-conditioning systems, e.g. heating systems, cooling systems, and combination heating/cooling systems, related and unrelated to vehicle applications if desired.

The heat exchanger 100 includes a first manifold 112, a second manifold 114, and a conditioning assembly 116 extending between the first manifold 112 and the second manifold 114. Each of the first manifold 112 and the second manifold 114 can be formed from any material and by any process as desired. In certain embodiments, the first manifold 112 and the second manifold 114 are formed by injection-molding a plastic material. In other embodiments, the first manifold 112 may be formed from a material of sufficient strength so that a wall thickness of the first manifold 112 can be minimized, thereby enhancing heat transfer between the first fluid in the first manifold 112 and the second fluid. For example, the first manifold 112 can be formed from aluminum, which is a material with desirable heat-conducting characteristics and sufficient strength characteristics. Various other materials can be used to form the first manifold 112 and the second manifold 114 if desired.

An inlet 118 of the first manifold 112 is in fluid communication with the fluid-conditioning system and receives the first fluid which has been heated by an external component (i.e. the engine) thereof. The heated first fluid flows through the first manifold 112 and into the conditioning assembly 116. The conditioning assembly 116 shown includes a plurality of tubular elements 120 extending between the first manifold 112 and the second manifold 114. An inlet opening 121 and an outlet opening (not shown) of each of the tubular elements 120 is fluidly connected to the first manifold 112 and the second manifold 114, respectively. The tubular elements 120 are arranged in parallel and spaced apart at substantially equal distances so that substantially constant gaps 122 are formed between adjacent tubular elements 120.

The second fluid flows through the gaps 122 between the tubular elements 120 to cool the heated first fluid flowing through the tubular elements 120. The flow of the second fluid through the conditioning assembly 116 may be caused by a movement of the vehicle and/or by a device which causes the second fluid to flow through the conditioning assembly 116 of the heat exchanger 110 such as a fan, for example. In certain embodiments, the gaps 122 may be provided with at least one heat transfer element 124. Various heat transfer elements 124 can be employed such as thin folded metal elements or fins, for example. The heat transfer elements 124 are arranged to abut the tubular elements 120, thereby increasing a contact surface of the tubular elements 120 with the second fluid to maximize a heat transfer from the first fluid to the second fluid. Each of the tubular elements 120 and the heat transfer elements 124 can be formed from any suitable material such as a metal (e.g. aluminum, copper, brass, magnesium, etc.) or other materials which have desired heat-conducting characteristics. The second manifold 114 receives the cooled first fluid from the respective tubular elements 120 of the conditioning assembly 116, after which the cooled first fluid is discharged from the second manifold 114 to the fluid-conditioning system via an outlet 126.

As illustrated, the first manifold 112 has a generally rectangular shape and includes a first end 146 and a second end 148. It is understood, however, that the first manifold 112 can have any shape and size as desired. In certain embodiments, the first manifold 112 includes a pair of opposing end walls 150, 152, a pair of opposing side walls 154, 156, and a back wall 158 opposite the inlet openings 121 of the tubular elements 120. The walls 150, 152, 154, 156, 158 define an opening configured to receive a portion of the conditioning assembly 116 and a chamber 157 configured to receive the first fluid therein.

As illustrated, the first manifold 112 includes a generally tapered first portion 159 and a generally tapered second portion 160. The generally tapered first portion 159 of the first manifold 112 is configured to distribute at least a portion of the first fluid into the tubular elements 120 adjacent the first end 146 of the first manifold 112. The generally tapered second portion 160 of the first manifold 112 is configured to distribute at least a portion of the first fluid into the tubular elements 120 adjacent the second end 148 of the first manifold 112. Each of the generally tapered portions 159, 160 is also configured to increase a velocity of the flow of the first fluid into the tubular elements 120 of the first manifold 112. As a non-limiting example, the generally tapered second portion 160 is configured to distribute and increase the velocity of at least a portion of the first fluid flowing into the last ten (10) tubular elements 120 in respect of a general direction of flow of the first fluid through the first manifold 112. The configuration of the generally tapered second portion 160 of the first manifold 112 advantageously minimizes an amount of the first fluid remaining within the first manifold 112 and the tubular elements 120 after operation of the heat exchanger 100. Thus, the configuration of the generally tapered second portion 160 militates against an accumulation of cooled first fluid within the first manifold 112 and the tubular elements 120, and thereby ensures that the heated first fluid is able to flow through the second end 148 of the first manifold 112 and the tubular elements 120 adjacent thereof. As such, a difference in temperature between the tubular elements 120 adjacent the first end 146 of the first manifold 112 and the tubular elements 120 adjacent the second end 148 of the first manifold 112 is minimized. As a result, a potential for severe thermal stresses which may cause damage to the heat exchanger 100 is minimized.

In certain embodiments, a volume of the generally tapered first portion 159 of the first manifold 112 generally decreases in respect of the general direction of flow of the first fluid through the first manifold 112. It is understood that a rate of change of the volume of the generally tapered first portion 159 of the first manifold 112 can be variable or substantially constant as shown. Similarly, a volume of the generally tapered second portion 160 of the first manifold 112 generally decreases in respect of the general direction of flow of the first fluid through the first manifold 112. It is understood that a rate of change of the volume of the generally tapered second portion 160 of the first manifold 112 can be variable or substantially constant as shown. As shown, the rate of change of the volume of the generally tapered first portion 159 is less than the rate of change of the volume of the generally tapered second portion 160.

In other embodiments, a distance between an inner surface 162 of the back wall 158 which at least partially forms the generally tapered first portion 159 of the first manifold 112 and a plane B generally defined by the inlet openings 121 of the tubular elements 120 generally decreases along the generally tapered first portion 159 as a distance from the inlet 118 in the general direction of flow of the first fluid in the first manifold 12 increases. It is understood that a rate of change in the distance between the inner surface 162 of the back wall 158 and the plane B generally defined by the inlet openings 121 of the tubular elements 120 can be variable or substantially constant as shown. Similarly, a distance between the inner surface 162 of the back wall 158 which at least partially forms the generally tapered second portion 160 of the first manifold 112 and the plane B generally defined by the inlet openings 121 of the tubular elements 120 generally decreases along the generally tapered second portion 160 as the distance from the inlet 118 in the general direction of flow of the first fluid in the first manifold 112 increases. It is understood that a rate of change in the distance between the inner surface 162 of the back wall 158 and the plane B generally defined by the inlet openings 121 of the tubular elements 120 can be variable or substantially constant as shown. The rate of change in the distance between the inner surface 162 of the back wall 158 of the generally tapered first portion 159 and the plane B is less than the rate of change in the distance between the inner surface 162 of the back wall 158 of the generally tapered second portion 160 and the plane B.

A fluid drain feature 170 may be formed in the generally tapered second portion 160 of the first manifold 112. As illustrated, the fluid drain feature 170 is integrally formed with the generally tapered second portion 160 of the first manifold 112. However, those skilled in the art will appreciate that the fluid drain feature 170 can be separately formed from the first manifold 112 if desired. It is also understood that the fluid drain feature 170 can be formed elsewhere in the heat exchanger 100 if desired. The fluid drain feature 170 can be formed with the generally tapered second portion 160 of the first manifold 112 by any suitable forming process such as an injection-molding forming process, for example. In certain embodiments, the fluid drain feature 170 is a portion 171 of the back wall 158 extending laterally outwardly from the generally tapered second portion 160 of the fluid manifold 112. The portion 171 of the back wall 158 shown is contoured to define a cavity 172. An aperture 174 is formed in the back wall 158 to permit the first fluid to flow, either directly or through an external component (i.e. fitting) or system, from the cavity 172 to a collection tank (not shown). In certain embodiments, the portion 171 of the back wall 158 at least partially surrounds the aperture 174. As illustrated, a hydraulic diameter of the cavity 172 is substantially the same as a hydraulic diameter of the aperture 174, thereby minimizing a volume of the cavity 172. The fluid drain feature 170 is configured to minimize the volume of the cavity 172 in order to minimize an amount of the first fluid remaining in the cavity 172 after operation of the heat exchanger 100. As discussed hereinabove, minimizing the amount of first fluid remaining in the first manifold 112 advantageously militates against an accumulation of cooled first fluid within the first manifold 112 and the tubular elements 120, and thereby ensures that the heated first fluid is able to flow through the second end 148 of the first manifold 112 and the tubular elements 120 adjacent thereto. As a result, the potential for severe thermal stresses which may cause damage to the first manifold 112, the tubular elements 120 adjacent the second end 148 of the first manifold 112, and/or a joint formed between the first manifold 112 and the tubular elements 120 is further minimized.

During operation of the heat exchanger 100, a heated first fluid from the fluid-conditioning system is received into the chamber 157 of the first manifold 112 through the inlet 118. As the first fluid flows from the first end 146 of the first manifold 112 through the chamber 157 and into the second end 148 of the first manifold 112, the generally tapered first portion 159 and the generally tapered second portion 160 of the first manifold 112 direct and increase the velocity of the flow of the first fluid into the tubular elements 120 adjacent thereto. More particularly, the generally tapered second portion 160 of the first manifold 112 ensures that at least a portion of the heated first fluid flows into the inlet openings 121 of the tubular elements 120 adjacent the second end 148 of the first manifold 112. Once the first fluid flows into the tubular elements 120 of the conditioning assembly 116, the first fluid undergoes a main conditioning by the second fluid flowing through the conditioning assembly 116. The conditioned first fluid then flows from the conditioning assembly 116 through the outlet openings thereof into the second manifold 114. The conditioned first fluid is then discharged from the heat exchanger 100 through the outlet 126 into the fluid-conditioning system.

From the foregoing description, one ordinarily skilled in the art can easily ascertain the essential characteristics of this invention and, without departing from the spirit and scope thereof, can make various changes and modifications to the invention to adapt it to various usages and conditions. 

What is claimed is:
 1. A heat exchanger, comprising: a conditioning assembly including a plurality of tubular elements configured to receive a flow of a fluid therein, each of the tubular elements having an inlet opening and an outlet opening formed therein; and a manifold coupled to the conditioning assembly, the manifold including a first end having an inlet formed therein and a second end opposite the first end, wherein the manifold is formed by at least one wall, and wherein a generally tapered portion of the manifold and a fluid drain feature located in the generally tapered portion of the manifold are configured to minimize an amount of the fluid remaining in at least one of the manifold and the tubular elements after operation of the heat exchanger, and wherein at least one of a volume of the generally tapered portion of the manifold and a distance between an inner surface of a wall opposite the inlet openings of the tubular elements and a plane generally defined by the inlet openings of the tubular elements generally decreases along the generally tapered portion of the manifold as a distance from the inlet increases.
 2. The heat exchanger of claim 1, wherein the generally tapered portion of the manifold at least one of directs and increases a velocity of the flow of the fluid into the last ten (10) tubular elements of the conditioning assembly.
 3. The heat exchanger of claim 1, wherein the fluid drain feature is integrally formed with the manifold.
 4. The heat exchanger of claim 1, wherein the fluid drain feature extends laterally outwardly from the generally tapered portion of the manifold.
 5. The heat exchanger of claim 1, wherein the fluid drain feature includes a cavity formed by a portion of the wall of the manifold opposite the inlet openings of the tubular elements.
 6. The heat exchanger of claim 5, wherein the fluid drain feature includes an aperture at least partially surrounded by the portion of the wall of the manifold opposite the inlet openings of the tubular elements.
 7. The heat exchanger of claim 6, wherein a hydraulic diameter of the cavity is substantially the same as a hydraulic diameter of the aperture.
 8. A heat exchanger, comprising: a conditioning assembly including a plurality of tubular elements configured to receive a flow of a fluid therein, each of the tubular elements having an inlet opening and an outlet opening formed therein; and a manifold coupled to the conditioning assembly, the manifold including a first end having an inlet formed therein and a second end opposite the first end, wherein the manifold is formed by at least one wall, and wherein a generally tapered portion of the second end of the manifold is configured to minimize an amount of the fluid remaining in at least one of the manifold and the tubular elements after operation of the heat exchanger, and wherein at least one of a volume of the generally tapered portion of the second end of the manifold and a distance between an inner surface of a wall opposite the inlet openings of the tubular elements and a plane generally defined by the inlet openings of the tubular elements generally decreases along the generally tapered portion of the manifold as a distance from the inlet in a general direction of the flow of the fluid through the manifold increases, and wherein the manifold further includes a fluid drain feature extending laterally outwardly from the generally tapered portion of the second end of the manifold.
 9. The heat exchanger of claim 8, wherein the generally tapered portion of the manifold at least one of directs and increases a velocity of the flow of the fluid into the last ten (10) tubular elements of the conditioning assembly.
 10. The heat exchanger of claim 8, wherein the fluid drain feature is integrally formed with the generally tapered portion of the second end of the manifold.
 11. The heat exchanger of claim 8, wherein the fluid drain feature includes a cavity formed by a portion of a wall of the manifold opposite the inlet openings of the tubular elements.
 12. A heat exchanger, comprising: a conditioning assembly including a plurality of tubular elements configured to receive a flow of a fluid therein, each of the tubular elements having an inlet opening and an outlet opening formed therein; and a manifold coupled to the conditioning assembly, the manifold including a first end having an inlet formed therein and a second end opposite the first end, wherein the manifold is formed by at least one wall, and wherein at least one of a generally tapered first portion of the first end of the manifold and a generally tapered second portion of the second end of the manifold is configured to minimize an amount of the fluid remaining in at least one of the manifold and the tubular elements after operation of the heat exchanger, and wherein at least one of a rate of change in a volume of the generally tapered first portion is less than a rate of change in a volume of the generally tapered second portion and a rate of change in a distance between an inner surface of a wall opposite the inlet openings of the tubular elements which defines the generally tapered first portion and a plane generally defined by the inlet openings of the tubular elements is less than a rate of change in a distance between an inner surface of a wall opposite the inlet openings of the tubular elements which defines the generally tapered second portion and the plane generally defined by the inlet openings of the tubular elements.
 13. The heat exchanger of claim 12, wherein the rate of change in the volume of the generally tapered first portion of the manifold is one of substantially constant and variable.
 14. The heat exchanger of claim 12, wherein the rate of change in the volume of the generally tapered second portion of the manifold is one of substantially constant and variable.
 15. The heat exchanger of claim 12, wherein the rate of change in the distance between the inner surface of the wall opposite the inlet openings of the tubular elements which defines the generally tapered first portion and the plane generally defined by the inlet openings of the tubular elements is one of substantially constant and variable.
 16. The heat exchanger of claim 12, wherein the rate of change in the distance between the inner surface of the wall opposite the inlet openings of the tubular elements which defines the generally tapered second portion and the plane generally defined by the inlet openings of the tubular elements is one of substantially constant and variable.
 17. The heat exchanger of claim 12, wherein the volume of the generally tapered first portion of the manifold generally decreases as a distance from the inlet in a general direction of the flow of the fluid through the manifold increases.
 18. The heat exchanger of claim 12, wherein the distance between the inner surface of the wall opposite the inlet openings of the tubular elements which defines the generally tapered first portion of the manifold and the plane generally defined by the inlet openings of the tubular elements generally decreases as a distance from the inlet in a general direction of the flow of the fluid through the manifold increases.
 19. The heat exchanger of claim 12, wherein the volume of the generally tapered second portion of the manifold generally decreases as a distance from the inlet in a general direction of the flow of the fluid through the manifold increases.
 20. The heat exchanger of claim 12, wherein the distance between the inner surface of the wall opposite the inlet openings of the tubular elements which defines the generally tapered second portion of the manifold and the plane generally defined by the inlet openings of the tubular elements generally decreases as a distance from the inlet in a general direction of the flow of the fluid through the manifold increases. 